/* 全局样式 */
:root {
    --primary-color: #0d6efd;
    --success-color: #198754;
    --danger-color: #dc3545;
    --warning-color: #ffc107;
    --info-color: #0dcaf0;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #f8f9fa;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

main {
    flex: 1;
}

/* 导航栏 */
.navbar-brand {
    font-size: 1.5rem;
}

/* 统计卡片 */
.stat-card {
    border: none;
    border-radius: 10px;
    transition: transform 0.2s, box-shadow 0.2s;
}

.stat-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
}

.stat-card .stat-icon {
    font-size: 2.5rem;
    opacity: 0.3;
}

.stat-total {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.stat-active {
    background: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    color: white;
}

.stat-completed {
    background: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
    color: white;
}

.stat-overdue {
    background: linear-gradient(135deg, #fa709a 0%, #fee140 100%);
    color: white;
}

/* 待办事项卡片 */
.todo-card {
    border: none;
    border-radius: 10px;
    transition: all 0.3s;
    border-left: 4px solid #0d6efd;
}

.todo-card:hover {
    box-shadow: 0 5px 15px rgba(0,0,0,0.15);
    transform: translateX(5px);
}

.todo-card.completed {
    opacity: 0.7;
    border-left-color: #198754;
}

.todo-card.overdue {
    border-left-color: #dc3545;
    background-color: #fff5f5;
}

.todo-card .form-check-input {
    width: 1.5rem;
    height: 1.5rem;
    cursor: pointer;
}

.todo-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-top: 0.5rem;
}

/* 优先级徽章 */
.priority-urgent {
    background-color: #dc3545;
    color: white;
}

.priority-high {
    background-color: #fd7e14;
    color: white;
}

.priority-medium {
    background-color: #ffc107;
    color: #000;
}

.priority-low {
    background-color: #6c757d;
    color: white;
}

/* 卡片样式 */
.card {
    border-radius: 10px;
    border: none;
}

.card-header {
    border-radius: 10px 10px 0 0 !important;
}

/* 列表组 */
.list-group-item.active {
    background-color: #0d6efd;
    border-color: #0d6efd;
}

/* 按钮样式 */
.btn {
    border-radius: 8px;
    padding: 0.5rem 1rem;
    transition: all 0.3s;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
}

/* 表单控件 */
.form-control, .form-select {
    border-radius: 8px;
    border: 1px solid #ced4da;
    transition: all 0.3s;
}

.form-control:focus, .form-select:focus {
    border-color: #0d6efd;
    box-shadow: 0 0 0 0.2rem rgba(13,110,253,.25);
}

/* 页脚 */
footer {
    margin-top: auto;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .stat-card {
        margin-bottom: 1rem;
    }
    
    .todo-card .btn-group {
        width: 100%;
    }
    
    .todo-card .btn-group .btn {
        flex: 1;
    }
}

/* 加载动画 */
.fade-in {
    animation: fadeIn 0.5s;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* 空状态 */
.empty-state {
    padding: 3rem;
    text-align: center;
}

.empty-state i {
    font-size: 5rem;
    color: #dee2e6;
}

/* 徽章样式 */
.badge {
    padding: 0.35em 0.65em;
    font-weight: 500;
}

/* 阴影效果 */
.shadow-sm {
    box-shadow: 0 0.125rem 0.25rem rgba(0,0,0,0.075) !important;
}

/* 自定义滚动条 */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: #f1f1f1;
}

::-webkit-scrollbar-thumb {
    background: #888;
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: #555;
}

/* 提示信息 */
.alert {
    border-radius: 10px;
    border: none;
}

/* 模态框 */
.modal-content {
    border-radius: 10px;
    border: none;
}

.modal-header {
    border-radius: 10px 10px 0 0;
}

/* 颜色选择器 */
.form-control-color {
    height: 45px;
    cursor: pointer;
}

